The work deals with the influence of water corrosion on the surface properties of inorganic-organic SiO₂ films, which were prepared from the sols in "tetraethoxysilane- isopropyl alcohol-water-nitric acid-triethoxy(octyl)silane" system. The atomic force microscopy and sessile drop technique was used on the characterization of surface properties. The morphology, rms-roughness, adhesion force and stiffness of prepared films were evaluated. Surface free energy and its polar and dispersion component were calculated by Owens-Wendt method using contact angles of distilled water and diiodomethane. The influence of corrosion on all of the studied properties of films was significant in the case of films prepared from sol with molar ratio of x(H₂O) : x(SiO₂) = 2.